Water hyacinth. By : Putri Wahyuni Siburian

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1 Water hyacinth By : Putri Wahyuni Siburian

2 Introduction

3 1.1. Description Water hyacinth consist of a free-floating rosette of shiny rounded leaves with thick masses of feathery roots which hang in the water. The roots are dark in colour and can reach 2.5 m in length. A single flowering stalk with cluster color of mauve or blue flowers with yellow spot that produced from the rosette. The stalk grows up to 50 cm above the leaf canopy.

4 1.2. Taxonomy Kingdom : Plantae Division : Magnoliophyta Class : Liliopsida Order : Commelinales Family : Pontederiaceae Genus : Eichornia Species : Eichornia Crassipes Rizk dan Pav (1991)

1.3. Life cycle Flowering can begin as early as October and continue through the summer months. Each of the flowers on a stalk remain open for one to two days before beginning to wither.

5 1.3. Life cycle Flowering can begin as early as October and continue through the summer months. Each of the flowers on a stalk remain open for one to two days before beginning to wither. When all the flowers on a plant have withered, the stalk gradually bends into the water. Seeds are released from capsules at the base of each dead flower after about 18 days. In warm climates, vegetative reproduction is rapid and enables the formation of large, dense rafts of plants within a short time.

1.4. Habit Water hyacinth is a perennial aquatic herb that can grow in still or slow-flowing fresh water in tropical and subtropical climates, and even in temperate regions with milder winters.

6 1.4. Habit Water hyacinth is a perennial aquatic herb that can grow in still or slow-flowing fresh water in tropical and subtropical climates, and even in temperate regions with milder winters. Its optimum growth occurs between 28 C and 30 C, and requires abundant nitrogen, phosphorus and potassium. However, it can tolerate a wide range of growth conditions. It is widely prevalent in tropical and subtropical waters enriched by agricultural runoff, untreated wastes and deforestation. It is especially pervasive in Southeast Asia, the southeastern United States, central and western Africa and Central America due to suitable growing conditions and the lack of natural predators.

7 1.5. Morphology A : The attenuated-petiole rosette form produced in crowded conditions; B : An expanding axillary bud; C : A developing ramet; D : The bulbous-petiole rosette form produced in open conditions. ar adventitious root; bb bud bract; in inflorescence; is leaf isthmus; la leaf blade; Pl primary leaf; pd peduncle of flower spike; pt leaf petiole; rh rhizome; sp spathe; st stolon.

Leaves Leaves are bright green, waxy, smooth and fleshy. They occur as a rosette at the base of the plant and consist of two parts a petiole (leaf stalk) and a leaf blade.

The leaf stalk is thick and spongy with bladder like swellings, which helps to keep the plant buoyant.

8 Leaves Leaves are bright green, waxy, smooth and fleshy. They occur as a rosette at the base of the plant and consist of two parts a petiole (leaf stalk) and a leaf blade. The leaf blade has smooth edges, is glossy, circular to heart-shaped and up to 30 cm in diameter. The leaves are held upright by swollen stems so they act like sails. The leaf stalk is thick and spongy with bladder like swellings, which helps to keep the plant buoyant. Leaves with bulbous petioles Leaves with non-bulbous petioles Enlarged/swollen petioles up to 25 cm long. This type of leaf is more characteristic of plants growing in infestations with low plants numbers or along the open-water edge of infestations. Leaves are up to 60 cm long, slender and erect. This leaf type is more typical of plants in crowded, dense infestations.

Flowers Each flower is funnel-shaped, has 6 petals, is bluish-purple in colour, 4 7 cm long and 4 6 cm wide. The upper petal is a deeper purple with a yellow spot in the centre.

9 Flowers Each flower is funnel-shaped, has 6 petals, is bluish-purple in colour, 4 7 cm long and 4 6 cm wide. The upper petal is a deeper purple with a yellow spot in the centre. Flowers are able to self fertilise and under ideal conditions, can appear throughout the year. Individual flowers only last a few days. Once all of the flowers on the spike have matured and withered, generally after about 18 days, the spike bends down into the water and releases its seeds.

Stems Erect up to 600mm long and bearing flowers or short, up to 100mm long on which new plants are produced.

Roots Roots are black to purple in colour, fine, fibrous and feather-like.

In nutrient rich water, roots are usually much shorter.

10 Stems Erect up to 600mm long and bearing flowers or short, up to 100mm long on which new plants are produced. Horizontal vegetative stolons, or runners, about 10 cm longthat produce new plants. Roots Roots are black to purple in colour, fine, fibrous and feather-like. In deep water they can be up to 1 m long and may trail freely behind the plant. In nutrient rich water, roots are usually much shorter. In shallow water the roots may become attached to the muddy bottom, allowing the plant to persist for several weeks after water levels drop. Fruit and seeds The seed capsule is narrow and cm long, containing up to 300 oval-shaped seeds that are mm long.

1.6. Distribution Distribution of water hyacinth (orange indicates the presence of water hyacinth). Image adapted from Téllez, T., López, E., Granado, G., Pérez, E.

11 1.6. Distribution Distribution of water hyacinth (orange indicates the presence of water hyacinth). Image adapted from Téllez, T., López, E., Granado, G., Pérez, E., López, R. & Guzmán, J., Originally from the Amazon Basin, its entry into Africa, Asia, Australia, and North America was facilitated by human activities (Dagno, et al., 2012).

12 1.7. Habitat Water hyacinth prefers still or slow-moving freshwater systems such as ponds, dams, lakes, rivers and wetlands. Plants require a body of water to establish and spread, but can also survive for many months on damp soil where water levels have receded. While it does require optimal conditions for rapid growth and spread, it is able to withstand a wide range of climates and conditions.

Temperature The ideal temperature for water hyacinth growth is 28 30 C,

35 C. Preferring tropical or sub-tropical climates, it can comfortably

13 Temperature The ideal temperature for water hyacinth growth is C, but it can still maintain good growth rates at temperatures between 22 and 35 C. Preferring tropical or sub-tropical climates, it can comfortably grow in temperate climates, but temperatures below 10 C will slow or stop growth. It can survive mild frosting, but severe frosts and prolonged cold weather may result in plant death. Seeds however, can successfully survive winter.

15 NOTE: May be confused with emergent form of the native frog s bit (Limnobium spongia), but its petioles not inflated and its flowers small, white, single in leaf axils.

Seeds are typically responsible for reinvasion of an area already treated. New plants can flower within 3 4 weeks, producing thousands of seeds that are released into the water.

16 1.8. Reproduction Water hyacinth can reproduce from both seed and vegetative growth. Under favourable conditions, water hyacinth is capable of growth and reproduction all year round, although flowering mostly occurs during spring and summer months. Seeds are typically responsible for reinvasion of an area already treated. New plants can flower within 3 4 weeks, producing thousands of seeds that are released into the water. The small seeds sink to the muddy bottom where they can remain dormant for up to 20 years. Once the water body has refilled, seedlings break free from the mud and float to the water surface, quickly developing a new root system. Vegetative growth is the most common form of reproduction and is largely responsible for the rapid growth and spread within an infestation. Daughter plants are produced from horizontal stolons that quickly develop root systems. Daughter plants eventually become independent from the mother plant when the connecting stolon decays or breaks. Vegetative growth can occur all year, but is most prolific during the spring and summer months.

18 Water hyacinth disaster First, let me take a selfie!!

Why is water hyacinth a pest? Water hyacinth (Eichhornia crassipes) is one of the world s most serious water weeds because of its aggressive fast-growing nature.

19 Why is water hyacinth a pest? Water hyacinth (Eichhornia crassipes) is one of the world s most serious water weeds because of its aggressive fast-growing nature. Plants can form dense mats that reduce the water quality, change water flows and increase sediment. Water hyacinth crowds out native aquatic plants and animals, altering ecosystems, destroying habitats, and blocking irrigation systems. Water hyacinth is being eradicated under the National Interest Pest Response programme funded and led by the Ministry for Primary Industries in partnership with regional councils and the Department of Conservation. It is both a notifiable organism and an unwanted organism under the Biosecurity Act 1993 and is banned from sale, propagation and distribution. Water hyacinth has been identified by the International Union for Conservation of Nature (IUCN) as one of the 100 most aggressive invasive species (Téllez et al., 2008) and recognized as one of the top 10 worst weeds in the world (Shanab et al., 2010, Gichuki et al., 2012, Patel, 2012). It is characterised by rapid growth rates, extensive dispersal capabilities, large and rapid reproductive output and broad environmental tolerance (Zhang et al., 2010). Legal status: Declared Pest, Prohibited Prohibited organisms are declared pests and permit conditions applicable to some species may only be appropriate or available to research organisations or similarly secure institutions. State prohibited weeds are the highest category of declared noxious weeds.

water hyacinth is capable of growth and reproduction all year round and have good assimilate with any condition.

20 Why water hyacinth is growing so fast??? In fact, water hyacinth is commonly called the fastest growing plant in the world. Within a year a single plant could produce million offspring ; and increase its volume 67 million times. The plant doesn't just reproduce by growing vegetatively but also produces seeds. water hyacinth is capable of growth and reproduction all year round and have good assimilate with any condition. Lots of them that can survive for many years without germinating, making eradication of the plant a near-impossibility. The seeds are sticky, which may help the plant spread: sticky seeds can catch a free ride on birds' feet and feathers, for instance. Water hyacinth has an extremely persistent seed bank, with studies indicating that seed viability can range from 5 to over 30 years in suitable conditions. Water hyacinth is an aggressive invader. An infestation can double in size every 5 days under ideal conditions. While seeds may not be viable at all sites, water hyacinth commonly colonises new areas through vegetative reproduction and propagation of horizontally growing stolons. It is not restricted to shallow water, unlike many submersed and emergent macrophytes, because its roots are free-floating near the surface (Villamagna and Murphy, 2010).

Dispersal Throughout a catchment, the greatest method of dispersal is from the movement of plants during periods of high water flow and flooding.

Seeds can be responsible for the introduction of water hyacinth into a new area, which may be moved by water or from contaminated mud stuck to birds, machinery or footwear.

21 Dispersal Throughout a catchment, the greatest method of dispersal is from the movement of plants during periods of high water flow and flooding. Large floating mats can break up and move to new areas within a catchment, and then rapidly increase in size from vegetative growth. A single plant can begin a new infestation. Seeds can be responsible for the introduction of water hyacinth into a new area, which may be moved by water or from contaminated mud stuck to birds, machinery or footwear. Birds may also be capable of moving small plants from dams and ponds into nearby waterways. Most spread has been the result of human activity, such as deliberate plantings and dumping of unwanted plants into waterways and possesses the greatest risk of developing new infestations. Despite a national ban on sale, it still remains a popular pond ornamental. New incursions are being found on the dams of lifestyle block in semi-rural and peri-urban areas. Contaminated fishing equipment, water craft and boat trailers is potentially another means of spread between water bodies.

22 Threat?

23 Threat related to ecosystems Loss of biodiversity Under high nutrient water levels, the growth of water hyacinth is dramatic, where it can quickly cover the entire water surface. Submerged plant communities are affected by the thick floating water hyacinth mats, as they block sunlight and absorb large amounts of nutrients that are required by these organisms to photo synthesise. This destruction of native habitat can lead to decreased fish, aquatic invertebrate and water bird populations as the availability of food diminishes. From picture beside lines represent verified relationships between ecological and dashed lines represent potential relationships that have yet to be documented.

Threat related to economic impacts Multimillion-dollar flood control and water supply projects can be rendered useless by waterhyacinth infestations (Gowanloch and Bajkov, 1948).

Shifting waterhyacinth mats sometimes prevent boats from reaching shore, trapping the occupants and exposing them to environmental hazards (Gowanloch and Bajkov, 1948; Harley, 1990). Center et al.

24 Threat related to economic impacts Multimillion-dollar flood control and water supply projects can be rendered useless by waterhyacinth infestations (Gowanloch and Bajkov, 1948). Infestations block access to recreational areas and decrease waterfront property values, oftentimes harming the economies of communities that depend upon fishing and water sports for revenue. Shifting waterhyacinth mats sometimes prevent boats from reaching shore, trapping the occupants and exposing them to environmental hazards (Gowanloch and Bajkov, 1948; Harley, 1990). Center et al. (2002) provided a summary of some of the costs associated with water hyacinth invasions losses of $43 million US dollars in 1956 to water hyacinth infestations in Florida, Mississippi, Alabama, and Louisiana. Florida spent more than $43 million US dollars during 1980 to 1991 to suppress water hyacinth and waterlettuce. Annual costs for water hyacinth management ranged from $500,000 in California to $3 million in Florida; and Louisiana herbicidally treats about 25,000 acres of water hyacinth per year, mostly at boat ramps, at an annual cost of $2 million US dollars.

25 Threat related to ecology Water quality Water quality is affected in a number of ways following water hyacinth invasion. Dissolved oxygen levels are reduced beneath the floating mat by decreasing the natural transfer of oxygen from the air at the water surface. In addition, decomposing dead plant material can further reduce the amount of dissolved oxygen and increase the amount of sedimentation and silting in the water. All of these factor lead to a decrease in water quality. The decreased water oxygen levels results in a changed aquatic habitat, as it reduces fish diversity and impacts on other aquatic flora and fauna communities. Water loss The amount of water lost from a water body by a water hyacinth infestation can be up to three times larger than the natural evaporation rate of an uncovered water surface. These high levels are the result of high transpirations rates water lost through the leaves. This can have large impacts on water storages with infestations of water hyacinth and river systems that may already be low on water.

26 Real case Water Hyacinth in Winam Gulf, in the northeast corner of Lake Victoria in Kenya. Source: NASA NASA reports: These images show the Winam Gulf, in the northeast corner of Lake Victoria in Kenya. The gulf was the most severely affected region during the first hyacinth outbreak in 1998, with as much as 17,231 hectares (67 square miles) of the plant growing on its surface. By 2000, the area covered by water hyacinth was down to about 500 hectares (2 square miles), and in December 2005, when the right image was taken, the lake appeared to be clear. In November and December 2006, however, unusually heavy rains flooded the rivers that feed into the Winam Gulf. The rain and floods raised water levels on the lake and swept agricultural runoff and nutrient-rich sediment into the water. As a result, the Winam Gulf was brown when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA s Terra satellite took the top left photo-like image on December 18, Vegetation around the lake was dramatically greener due to the rains.

27 Threat related to infrastructure During flood events, large mats of water hyacinth can move with flood waters. These large mats can be very heavy, up to 450 tonnes of wet weight per hectare, which can build up against, and cause damage to, bridges, culverts, roads and fences. This may obstruct the natural flow of water and possibly increase flood levels, contributing to the loss of infrastructure, livestock and equipment. Once flood waters subside, large mats of water hyacinth can be left stranded on crops and pastures, destroying the underlying plants, and can be very costly to remove.

Threat related to health and safety Water hyacinth mats can be dangerous for recreational users of water and stock which may become tangled in the roots

Mats may provide a breeding ground for mosquitos which can carry disease such as Ross River virus and Dengue fever.

28 Threat related to health and safety Water hyacinth mats can be dangerous for recreational users of water and stock which may become tangled in the roots and stolon of plants if venturing into the water. Canoeists and kayakers can risk being caught or entangled in mats if their craft capsizes. Mats may provide a breeding ground for mosquitos which can carry disease such as Ross River virus and Dengue fever. Bulk removal and stockpiling of harvested water hyacinth material that contains heavy metals may also pose a small risk if not managed correctly. Fun fact men survived from crash plane because of water hyacinth

Threat related to recreation and aesthetics Large mats formed on the waters surface can interfere with water activities such as boating, swimming and fishing.

Water hyacinth can completely block waterways, making water sports very difficult or dangerous.

29 Threat related to recreation and aesthetics Large mats formed on the waters surface can interfere with water activities such as boating, swimming and fishing. Passage of boats through waters infested with water hyacinth becomes difficult, with plant material potentially clogging motors or getting caught in propellers. Water hyacinth can completely block waterways, making water sports very difficult or dangerous. Swimming becomes dangerous, as swimmers may become entangled in the mass of roots and runners beneath the waters surface. Reduced fish populations as a result of heavy infestations can minimise recreational fishing activities. The natural beauty of an open water body can be greatly diminished by invasion of water hyacinth, as native plants, birds and aquatic animals are displaced. While water hyacinth may be an attractive water plant in small numbers, the implications it can have towards the environment and economy far outweigh any visual appeal. Picture below is Toba lake in Indonesia before and after water hyacinth infestation.

Threat related to agriculture Interference with irrigation and stock watering, Stock may have difficulty gaining access to water to drinking water if the surface is completely covered by weeds.

30 Threat related to agriculture Interference with irrigation and stock watering, Stock may have difficulty gaining access to water to drinking water if the surface is completely covered by weeds. Water flow to irrigation equipment is reduced to the restrictive action of the roots, which in turn increases pumping times and costs. Blockage of waterways hampering agriculture, fisheries, recreation and hydropower Water hyacinth often clogs waterways due to its rapid reproduction and propagation rate. The floating mats may limit access to breeding, nursery and feeding grounds for some economically important fish species (Villamagna and Murphy 2010). In Lake Victoria, fish catch rates on the Kenyan section decreased by 45% because water hyacinth mats blocked access to fishing grounds, delayed access to markets and increased costs (effort and materials) of fishing (Kateregga and Sterner 2009).

31 THIS IS THE SOLUTION

Prevention and early detection Regularly check water bodies for suspect plants and

Check high risk areas, including ponded or slow-moving water bodies, and areas

Control new infestations as quickly as possible When using water facilities make

32 Prevention and early detection Regularly check water bodies for suspect plants and have them identified. Check high risk areas, including ponded or slow-moving water bodies, and areas close to human activity and urban development. Control new infestations as quickly as possible When using water facilities make sure any related equipment is free of plant material prior to leaving. Community education to increase awareness, capacity for early detection and decrease the plants ornamental use.

herbicide coverage of the plant is achieved. 3. Timing of applications, herbicides should be applied before flowering to young green material that is experiencing active growth.

33 Chemical solution Herbicide, 1. All registered herbicides are applied as a foliar spray on actively growing plants. 2. Correct application, To get the best results from herbicides, it is important that they are applied as a foliar spray at the correct rate, at the right stage of plant growth and that complete herbicide coverage of the plant is achieved. 3. Timing of applications, herbicides should be applied before flowering to young green material that is experiencing active growth. plants experience most growth during the spring and summer months, with flowering normally starting early autumn Water hyacinth after spray with diquat, note some green petioles are appearing After aerial spray, note some water hyacinth was shielded from the herbicide by other vegetation

34 Herbicides registered for the control of water hyacinth Herbicide Registered use Application Rate Comments Diquat 200 Active constituent: Diquat 200 g/l Registered products: Desiquat Non-residual Herbicide Dia Kill 200 Herbicide Diquat 200 Herbicide Diquat 200 Nonresidual Herbicide Reglone Non-residual Herbicide Sanction 200 Nonresidual Herbicide Water hyacinth in aquatic areas Registered for use in all states Withholding period: Do not use treated water for human consumption, livestock watering or irrigation purposes for 10 days after application High volume spot spray, boom spray or aerial application DO NOT spray if plants are stressed or covered with dust or soil DO NOT spray with misting machines or CDA applicators Apply in dull weather or at the end of the day for best results 400 ml per 100 L of water 5 10 L/ha Apply as an overall spray wetting foliage thoroughly Use higher rates for heavy infestations or for deep or dirty water A repeat application may be necessary 7 14 days later for dense infestations Diquat Active constituent: Diquat 20 g/l Registered products: Vegetrol Herbicide Watrol Non-residual Herbicide Water hyacinth in aquatic areas Registered for use in all states Withholding period: Do not use treated water for human consumption, livestock watering or irrigation purposes for 10 days after application High volume spot spray DO NOT spray if plants are stressed or covered with dust or soil DO NOT spray with misting machines or CDA applicators 4.0 L per 100 L of water L/ha Apply as an overall spray. Thoroughly wet foliage. Do not apply to weeds covered in mud or dust

35 Herbicide Registered use Application Rate Comments Glyphosate Registered products: Numerous products registered specifically for use in aquatic areas Water hyacinth in aquatic areas Registered for use in all states High volume application with handgun, knapsack or boom DO NOT use additional surfactant unless stated in the label and it is approved for use in aquatic situations L/100 L water Apply to actively growing plants prior to flowering. Use higher rates on dense infestations Do not treat plants that are stressed or heavily covered in dust or silt Re-treatment may be required if plant becomes submersed or rain occurs within 2 hours of aplication 2,4-D acid Active constituent: 2,4-D 300 g/l Registered product: Affray 300 Herbicide Water hyacinth in waterways, nonpotable water, drains, dams, margins, lakes and streams Registered for use in NSW, Qld, WA and NT only Knapsack spray, High volume hand gun spray 1 L/200 L water Overall spray Coverage: 200 L spray solution/1000 m2 Spray prior to flowering Avoid causing submersion of sprayed plants Amitrole Active constituent: Amitrole 250 g/l Registered products: Aggrav8 Herbicide Amitat Herbicide Amitrole 250 Herbicide Amitrole T Herbicide Weedeath Water hyacinth in drains and channels, margins of streams, lakes and dams Registered for use in all states High volume spot spray 280 ml/100 L water Apply immediately prior to flowering

36 Application methods Sprinkler spraying Aerial application Boom spraying

37 Boat with spray unit Tractor with spray unit Hose and hand gun Knapsack spraying

Physical solution Manual removal This method involves manually removing water hyacinth by hand or with rakes and pitchforks or nets from a water body.

38 Physical solution Manual removal This method involves manually removing water hyacinth by hand or with rakes and pitchforks or nets from a water body. It is best suited for: small plant numbers that are in the early stages of an infestation, the removal of plants in small, confined areas such as garden ponds, small dams or drains, small numbers of scattered plants that are growing in shallow water or along the edges of a waterway, and follow-up to chemical or mechanical control to remove floating or newly germinated seedlings.

Mechanical removal Mechanical removal of water hyacinth requires purpose built aquatic weed harvesters that can either remove the bulk of the plant material from the water surface or break thick mats

39 Mechanical removal Mechanical removal of water hyacinth requires purpose built aquatic weed harvesters that can either remove the bulk of the plant material from the water surface or break thick mats apart and move them closer to the bank for removal by an excavator or other similar machinery. Limitations of mechanical removal: High equipment costs compared to chemical control. Some machinery is not suitable for shallow water or areas with accessibility issues or highly sensitive vegetation. Time consuming. Labour intensive.

Biological solution The weevils Neochetina eichhorniae Neochetina eichhorniae were the first agents

Adult are 4 5 mm long, grey in colour and very similar in appearance to N. bruchi.

Wing colour ranges between golden-yellow to charcoal grey, with brown, black and white markings.

40 Biological solution The weevils Neochetina eichhorniae Neochetina eichhorniae were the first agents released for the biocontrol of water hyacinth in Australia. Adult are 4 5 mm long, grey in colour and very similar in appearance to N. bruchi. Niphograpta albiguttalis Adult moths are 6 10 mm long and have a wing-span of mm. Wing colour ranges between golden-yellow to charcoal grey, with brown, black and white markings. They are difficult to see in the field. Neochetina bruchi First released into Australia in 1990, adult beetles are 4 5 mm long and tan brown in colour and only slightly larger than N. eichhorniae.

Weevil release strategies Adults or weevil infested material can be simply tipped from containers into the infestations. Ideally at least 250 weevils should be released together in one area.

41 Weevil release strategies Adults or weevil infested material can be simply tipped from containers into the infestations. Ideally at least 250 weevils should be released together in one area. The following factors should be considered when undertaking releases: Other controls: release sites should be located away from areas where herbicide or mechanical control methods occur as these methods may interfere with establishment. Plant condition: releases should be made on plants that are in good condition. Also select sites where the weed mat is stable and unlikely to be washed downstream. Aspect: weevils should be released into an open sunny area. Catchment location: weevils should be released as high up the catchment as possible except in impoundments where the weed will be concentrated near the dam wall which is a good place for release. Infestation size: in an extensive infestation it is best to undertake releases at multiple sites across the infestation area. Larger quantities of weevils will be required; as an example, if 1000 weevils were available divide them into 4 releases of 250 each. Weevils can be released into 1 1 m quadrats, which helps contain them whilst populations are growing.

42 There always be integrated control as a solution Biological and herbicide control Chemical and mechanical control

43 practical applications of water hyacinth handicraft Is it work??? Yes it is!!! (this example of water hyacinth handicraft centre in indonesia)

Fertilisers. Water hyacinth can be used on the land either as a green manure or as compost. As a green manure it can be either ploughed into the ground or used as a mulch.

Microbial decomposition breaks down the fats, lipids, proteins, sugars and starches.

44 Fertilisers. Water hyacinth can be used on the land either as a green manure or as compost. As a green manure it can be either ploughed into the ground or used as a mulch. The plant is ideal for composting. After removing the plant from the water it can be left to dry for a few days before being mixed with ash, soil and some animal manure. Microbial decomposition breaks down the fats, lipids, proteins, sugars and starches. The mixture can be left in piles to compost, the warmer climate of tropical countries accelerating the process and producing a rich pathogen free compost which can be applied directly to the soil. The compost increases soil fertility and crop yield and generally improves the quality of the soil. Charcoal briquetting. This is an idea which has been proposed in Kenya to deal with the rapidly expanding carpets of water hyacinth which are evident on many parts of Lake Victoria. The proposal is to develop a suitable technology for the briquetting of charcoal dust from the pyrolysis of water hyacinth. The project is still very much at the idea stage and both a technical and a socio economic study are planned to evaluate the prospects for such a project. It is suggested that a small-scale water hyacinth charcoal briquetting industry could have several beneficial aspects for the lakeside communities:

with paper production from water hyacinth for some years. Animal fodder.

rice bran, copra cake and salt to make a suitable feed.

45 Paper. The Mennonite Central Committee of Bangladesh has been experimenting with paper production from water hyacinth for some years. Animal fodder. Studies have shown that the nutrients in water hyacinth are available to ruminants. In China pig farmers boil chopped water hyacinth with vegetable waste, rice bran, copra cake and salt to make a suitable feed. In Malaysia fresh water hyacinth is cooked with rice bran and fishmeal and mixed with copra meal as feed for pigs, ducks and pond fish. Is it work??? Yes it is!!! (Alibaba.com Notebook for $5) Is it work??? Yes it is!!!

Biogas NASA has demonstrated that each 2.2 lbs. of water hyacinth (dry weight) yields about 83 gallons of biogas, with an average methane content of 69 per cent.

46 Biogas NASA has demonstrated that each 2.2 lbs. of water hyacinth (dry weight) yields about 83 gallons of biogas, with an average methane content of 69 per cent. Studies reported in m3 of biogas per m3 of digester per day, has been 0.52 during the warm season and 0.29 during the cool season. Although the yields have been quite satisfactory, they can be improved by applying the appropriate pretreatments. The facility can save 7.3 tonnes of firewood per year. Promoting the use of biogas will contribute to the fight against desertification. Using the water hyacinth as a substrate for the production of biogas is an advantageous control strategy because it permits a productive fight against the plant s invasion.

Weed Management Guide Weed of National Significance

Weed Management Guide Weed of National Significance Water hyacinth (Eichhornia crassipes) The distinct water hyacinth flower. Feeding scars from weevil activity can be seen on leaves. Photo: T Bickel.